Oil-engine-feeding device



F. G. HOBART.

OIL ENGINE FEEDING DEVICE.

APPLICATION FILED OCT-8,1917.

1,337,770. Patented Apr. 20, 1920,

W 4 SHEETS-SHEET I.

'F. G. HOBART.

01L ENGINE FEEDING DEVICE.

APPLICATION FILED OCT-8.1917.

1,337,770. I Patented Apr. 20, 1920.

4 SHEET$SHEET 2.

1 ml uawea/ X 6% C) F. G. HOBART.

0|L ENGINE FEEDING DEVICE.

APPLICATION FILED OCT- 8| 1917. 1,337,770. Patented Apr; 2%, 1920.

4 SHEETS-SWEET 3.

F. e. HOBART.

OIL ENGINE FEEDiNG DEVICE.

APPLICATION FILED OCT-8| 1917.

1,837,770. 'Patented A m 20, 1920.

4 SHEETSSHEET 4.

UNITED STATES PATENT OFFICE.

FRANKLIN G. HOBART, OF BELOIT, WISCONSIN, -ASSIGNOR TO FAIRBANKS, MORSE & COMPANY, OF CHICAGO, ILLINOIS, ACORPORATION OF ILLINOIS.

Specification of Letters Patent.

Patented Apr. 20, 1920.

Application filed October 8, 1917. Serial No. 195,254.

To all whom, it may concern:

Be it known that I, FRANKLIN Gr. HOBART, a citizen of the United States residing at Beloit, in the county of Rock and State of Wisconsin, have invented a certain new and useful Improvement in Oil-Engine-Feeding Devices, of which the following is a specification.

My invention relates to internal combustion engines, especially those of the Diesel and semi-Diesel type in which fuel oil is injected into the cylinders positively, at the proper time and particularly to multi cylinder engines. The object is to provide a simple arrangement by which a single cam is enabled to operate all of the fuel-injection pumps and another governor controlled cam to control the pump inlet valves. To illustrate: In a four cylinder engine, the combustion strokes do not, of course, occur simultaneously, but in sequence, the com bustion taking place first in one cylinder and then in another. In carrying out my invention, I have provided a rotating cam which actuates certain rollers which actuate the pump plungers, and have so distributed these angularly about a single cam thatthe pump plungers for the different cylinders operate in the proper sequence. In the illustrated embodiment of my invention, also, I regulate the timing of the fuel injection by providing another cam which rotates and is angularly advanced or retarded by a speed governor. This cam controls the inlet valves of the fuel pumps. the parts being so constructed that on the acting stroke of the plungers, the fuel will not be injected into the engine cylinders until the inlet valves close. As long as the inlet valves remain open, the fuel will be forced back past them, but as soon: as they close, the fuel will be forced into the engine cylinder. In carrying out my invention in the form illustrated I have so distributed the inlet valve operating mechanism angularly about the governor controlled cam that this single cam properly controls all of said inlet valves. I As an incident of this angular distribution of the pump mechanism, it isconvenient-to have all, the plungers and all the inlet valves reciprocate 1n approxi-; mately parallel and horizontal lines.

I have included in Figure 2 parts of a.- lubricating device for the parts Within the housing. This forms the subject of a separate application for lubricator filed jointly by Charles B. J ahnke and myself on the tenth day of October, 1917, issued August 13, 1918 as Patent No. 1,275,427.

I accomplish my present objects by the' 2-2, Fig. 1 and shows the mechanism which operates the fuel injector pump plungers for a four cylinder engine.

Fig. 3 is a vertical section on the line 3-3, Fig. 1 and shows the mechanism which operates the inlet valves of the fuel injector pumps.

Fig. 1 is a vertical section on the line H, Fig. 1 and shows a suitable type of governor for advancing or retarding the timing cam which operates the inlet valves.

Fig. 5 is a sectional detail on the line 5-5, Fig. 1. This shows the inlet and outlet valves of the pumps which I employ to pump the fuel oil from a general su ply tank to a small tank (not shown) om which the fuel oil flows by gravity to the fuel injector pump- Similar numerals refer to similar parts throughout the several views.

In the particular form selected to illustrate the invention, the fuel oil is supplied to the fuel injection pumps by gravity from a comparatively small local tank (not shown) located at or near the engine and slightly above the pumps. By preference, this local tank is kept supplied with fuel by a supply pump shown in Fig. 5, and at the upper left corner of Fig. 1. It consists of a casing 1 inclosing a plunger 2 operated from the engine shaft 3. "The shaft has an eccentric 4 encircled by a strap 5 which carries a pin 6 by which the strap is secured to the inner end of the plunger. A pipe 7 leads ,to the casing from the principal source of supply and a pipe 8 leads from the easing to the said local tank. Suitable inlet and outlet valves 9 and 10, respectively, are provided. .While there is an advantage in thus supplying oil to a local tank by a. pump locatedclose to the injecting mechanism and operated by the engine shaft, it will be understood that other means for supplying the fuel may be substituted.

In this type, designed for a four cylinder 'engine, there are four injection pumps, all

alike, and four inlet valves, all alike, the valves, in a sense, forming part of the pumps and serving to regulate the time of injec' tion. Each of the valve casings 11 is supplied with fuel oil by an inlet pipe 12 which leads from the said local tank. A valve seat 13 is formed in each casing and this cooperates withan inlet valve 14 (sometimes called a suction valve) which controls the flow to the passage 15 of the associated injector pump, presently to be described. Valve 14 is urged toward closed position by a helical compression spring 17. It is attached to a stem 18 which passes up through the casing 11. In case the fuel should creep up past the lower portion of stem 18, it passes off through a drain 19. The fuelwhich the injector pump delivers is conducted to the engine cylinders through pipes 20 which lead from the passages 15,

as shown in Fig. 2. A helical compression spring 21 acts upon each stem to urge the valve to close, and the stem is pushed in the opposite directionby a push rod 22.

Two of the four push'rods are acted upon directly by the timing cam 23 and two of them are operated indirectly by it as shown in Fig. 3. The ones indirectly. operated are actuated by rocker arms 25 pivoted upon' fulcrums 26 supported by lugs 27 formed on the inside of the housing 28. Said rocker arms are in the form of bell cranks and the parts are so arranged that all of the push rods are horizontal notwithstanding the fact that the rocker arms contact the uppermost and lowermost points of the timing cam and are moved vertically by it. The push rods which are operated directly engage the tim-- ing cam on opposite sides thereof, while the rocker arms engage the cam at intermediate points, top and bottom. This ar-.

rangement has two advantages. First, it makes it possible to have'all of the push rods lie horizontal so that the action and construction of the inlet valves and associated parts may be uniform, and second, it causes the camaction on any given push rod to occur'one quarter ofa revolution later than on the preceding one.' Thus it is. made possible to operate the push rods in-proper sequence and at pro er intervals of time by a single cam. By a -single cam, I mean not four cams formed integral with each other but a cam the same surface of which passes successively into cooperative relation with'the four different push rods. There is nothing, however, to prevent locating the various push rods in parallel planes; such arrangement would be less compact and economical.

The timing cam 23 is loose upon the shaft so as to be angularly movable relatively thereto, and it will be evident that'by advancing or retarding the cam, the time of closure of the inlet valve will be corre-. spondingly advanced or retarded, thus regulating the speed of the engine. Said cam is connected by pins 30 to the sleeve 31 parts areso constructed and related that when the speed of the shaft exceeds normal, the timing cam 22 will be rotated in one direction relatively to the shaft, and when the speed falls below normal, it will be rotated in the opposite direction.

The main injector pumps are four in numher, as mentioned, and are shown in Figs. 1 and 2. Each pump casing or cylinder 16 has a plunger 43 which is actuated indirectly by a roller 44 contacting the periphery of the pumping cam 45 rigidly secured to the engine shaft. Two of these rollers are located on opposite sides of the cam and mounted on a slide 46 which engages the innei" end of the plunger. The roller is kept in close contact with the cam by'a compression spring 47 which also serves to keep the inner end of the plunger in contact with the slide. The remaining two rollers 44 are preferably placed in the same plane as the others and located on the top and bottom of the'cam, halfway between the others. The lastmentioned rollers are mounted. on rocker arms 50 fulcrumed on the pins 51 carried by the lug 52 on the inside of the engage the inner end of the remaining two plungers 43. Springs 47 cooperate with these plungers in the manner previously described. As'a result of this arrangement it is possible to place all of the injector pumps in parallel (horizontal) position and the different plungers operate inproper sequence for their respective engine cylinders Thus, a single fixed cam serves to operate all of the injection pumps in proper sequence and with a proper interval of time between.

The operation Will now be readily understood. As the shaft rotates, it rotates the fixed cam 45 and causes the plungers to -reciprocate lin their respective casings in proper order for the respective cylinders. As long as the respective inlet valve 14 is open, the outwardly moving plunger will force the oil past the valve and into the connected supply pipe 12. As soon as the therefore, I am able, by -the aid timing cam 23 permits the valve to close, the fuel oil, which has no outlet except through the delivery duct 20, leads it to the engine cylinder, and forces it thereinto. Consequently, the movement of the plunger produces, under ordinary practical conditions, no injective effect, or substantially none, until the valve is closed;- and the time of closing the valve is regulated by the timing cam 23. As a result of my invention, of two cams, not only to inject the fuel into the cylinders of a four cylinder engine, but I am able also to control. the timing of the injection and thereby regulate the speed of the engine.

lVhile the co-acting parts within the h using 28 may be lubricated in any suitable manner, there is shown in Fig. 2 a simple and effective way of accomplishing it. The housing is made oil-tight and a certain quantity in the bottom, as shown. A pipe of comparatively small diametei' is led up through a bushing 61 screwed into the bottom of the housing. This pipe'extends up for a short distance into the housing and points toward the cams. It has a small inlet opening 62 near the bottom of the housing, below the level of the lubricating oil. Pipe 60 leads from a point inside of the crank case (not shown) of the engine. It is well known that it is common practice in internal combustion engines to have an inclosed crank case and that the movement of the pistons produces pulsations (alternate suction and compression) in this case. In the present construction, these pulsations produce corresponding pulsations of air in the pipe 60 and these pulsations forcibly eject from the inner mouth of the pipe such a quantity of lubricating oil as may enterthe pipe through the aperture 62. The result is that the pipe intermittently ejects lubricating oil onto the cam and thus lubricates them. The force of the ejection is sufficient to cause the oil to splash onto the other movable element in the housing and so all the parts are lubricated. This lubricator, however, is not herein claimed as it forms the subject of a co-pending application, as hereabove mentioned.

I have also produced simple and effective means for preventing the lubricating oil from escaping from the housing. By reference to the upper portion of Fig. 1 it will be seen that annular grooves 70 are formed in the end walls 71 of the-housing around shaft 3. Annular flanges 72 are formed upon the shaft and this projects into said of lubricating oil introduced grooves. In other words, I produce interiitting flanges and grooves which, by cooperation, prevent the lubricating oil from splashing through and escaping from the housing, yet the parts are not in actual contact and consequently avoid any friction losses.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. Mechanism for injecting fuel into a multi cylinder internal combustion engine, said mechanism including horizontally arranged pumps, a duct leading from each pump to the respective engine cylinder, a rotating cam, means contacting said cam at the end of a substantially horizontal radius for operating one of said pumps, and means including a rocker arm contacting said cam at the end of a substantially vertical radius for operating the other of said pumps.

2. Mechanism for injecting fuel into a multiple cylinder oil engine comprising one pump for each cylinder, a rotating cam operating one or more of the pumps by contact with a reciprocating slide and operat ing other pumps through rockers whereby said other pumps may be in non-radial positions and the operating points spaced about the cam at angular positions to properly time the introduction of fuel into each cylinder.

3. In combination, an engine shaft, a plurality of fuel injecting pumps all arranged horizontally, a cam rotated by said shaft, and means operated by said cam for actuating said pumps, said means including an element contacting the cam at the end of a substantially horizontal radius and an element contacting the cam at the endof a substantially vertical radius, and means at the end of said substantially vertical radius for converting vertical to horizontal movement.

4. Mechanism for injecting fuel into a four cylinder internal combusti -n engine, said mechanism including four pumps arranged parallel to each other, a rotating cam engaging two-of said pumps at the end of a diameter lying parallel withthe pumps, and two rocker arms engaging the cam at the end of a diameter lying at right angles to the pumps, said rocker arms actuating the pumps not actuated directly by the cam.

In witness whereof, I have hereunto subscribed my name.

FRANKLIN GQ HOBART. 

